This is something i would pay (more) for as a supporter and would not disadvantage non-supporters.
Either as a pay per "ebay" bid, or pay more for supporter to have it unlimited. The exact nature could depend on how much computer/people resources it takes up to run the feature
this will be an improved way of bidding which results in a more efficient outcome in terms of manager behaviour (more will bid the value to them) and for those out there who dont like "daytrading"/farming activities this in some circumstances may add an extra check.
im sure this isnt a new idea as its quite obvious to me, but i guess if enough people mention it, it might be looked at, especially if it raises some more money for the BB guys